U0680Lost Communication With Barometric Pressure Sensor B
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- The letter B need not mean a second ambient sensor; it can be any further pressure input that sees near-atmospheric air. GM's 23OBDG07 and 24OBDG07 tables, written for a program with two throttle bodies, use barometric sensor B for the pressure ahead of the bank 2 throttle and send it over SENT. U0680 is stored when the frames carrying the high and low line pressure of bank 2 come in with a wrong data length code for 1.5 s; the MIL follows after two trips. The checks of the value itself are P222C and P222D (raw reading under 50 or over 115 kPa) and P222B (plausibility against ambient pressure). U068A covers the bank 1 counterpart. Air mass on bank 2 then has to be estimated without its reference.
- What you may notice
- Check engine light after two trips
- Uneven running between banks possible
- Additional pressure plausibility codes
- Likely causes
- LikelySENT signal, supply or ground wire to the bank 2 pressure sensor faulty
- PossibleConnector at the sensor ahead of the throttle loose or wet
- PossiblePressure sensor sends malformed frames
- RareEngine controller software or SENT input fault
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €50 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.